This invention relates to a rotation sensor for detecting the number of revolutions of a gear-like magnetic rotation body, for example, and a manufacturing method therefor.
A rotation sensor for detecting the number of revolutions of a gear-like magnetic rotation body is proposed, for example, in Japanese Patent Laid-Open No. Hei 7-198736. In such sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused,by rotation of a magnetic rotation body, a terminal for outputting a signal of the magnetoelectric conversion device is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the terminal, a part of the terminal is used as a surface mount electrode to mount electronic components, the surface mount electrode part is provided by bending the terminal to produce a layered structure, and a connector part is formed using the terminal end as terminal electrode.
For the conventional rotation sensor, the base made of resin and the connector part of an insert conductor are simultaneously formed by insert-molding. Thus, the thus resin pressure at molding causes the insert conductor to be deformed and adjacent insert conductors to be short-circuited. To prevent the insert conductor from being deformed, the insert conductor needs to be sandwiched and held between pins disposed in a metal mold at a large number of points at molding. Resultantly, the insert conductor is exposed to the holding parts. Thus, seal material needs to be applied to the insert conductor exposure parts to prevent moisture entering from the outside from causing a short circuit. As a result workability is poor.
Further, the surface mount electrode part formed by the insert conductor is layered. To provide a layered structure, two or more bending steps are required and workability is poor.
To provide a layered structure, the electrode area before bending requires twice that after bending at each surface mount electrode, thus the number of surface mount electronic components cannot be increased and freedom of layout is restricted.
It is therefore an object of the invention to provide a rotation sensor having a simple structure manufactured simply at low costs with high reliability and excellent workability and a manufacturing method therefor.
According to the first aspect of the invention, there is provided a rotation sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the insert conductor, a part of the insert conductor is used as a surface mount electrode to mount electronic components, a connector part is formed using the insert conductor end as terminal electrode, a groove for mounting an O-ring is formed, and an O-ring is made to intervene between a case and the connector part, thereby sealing in the case.
According to the second aspect of the invention, there is provided a rotation sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the insert conductor, a part of the insert conductor is used as a surface mount electrode to mount electronic components, a connector part is formed using the insert conductor end as terminal electrode, and pockets are formed by forming walls surrounding interfaces produced to support the base when the connector part is molded, and are filled with an adhesive.
According to the third aspect of the invention, there is provided a rotation sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the insert conductor, a part of the insert conductor is used as a surface mount electrode to mount electronic components, a connector part is formed using the insert conductor end as terminal electrode, a groove corresponding to a joint of the insert conductor is formed, and recesses or projections are made on the outer peripheral surface of the groove.
According to the fourth aspect of the invention, there is provided a rotation sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, and the magnetoelectric conversion device is electrically connected to the insert conductor in a state in which it is sandwiched between positioning parts disposed at the tip of the base.
According to the fifth aspect of the invention, there is provided a rotation sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, and the magnetoelectric conversion device is pressed into a press fit part formed in the base for fixing leads of the magnetoelectric conversion device, then is electrically connected to the insert conductor.
According to the sixth aspect of the invention, there is provided a rotation sensor in that a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the insert conductor, a part of the insert conductor is used as a surface mount electrode to mount electronic components, a connector part is formed using the insert conductor end as terminal electrode, and the surface mount electrode part of the insert conductor is heightened with respect to peripheries.
According to the seventh aspect of the invention, there is provided a rotation sensor wherein a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a conductor for guiding output of the magnetoelectric conversion device to the outside is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the insert conductor, a part of the insert conductor is used as a surface mount electrode to mount electronic components, a connector part is formed using the insert conductor end as terminal electrode, and in a state in which the base is positioned by guides formed in a case made of resin having a mount part, the base and the case are fixed mutually.
According to the eighth aspect of the invention, there is provided a method of manufacturing a rotation sensor comprising the steps of stamping an insert conductor into a predetermined shape, insert-molding the stamped insert conductor in a base and cutting an unnecessary joint, molding a connector part in the base, connecting a magnetoelectric conversion device to the insert conductor, mounting surface mount electronic components on predetermined positions of the insert conductor, and inserting the base into a case, heat-caulking a case end, and fixing the base and the case mutually.
According to the ninth aspect of the invention, there is provided a method of manufacturing a rotation sensor comprising the steps of stamping an insert conductor into a predetermined shape, insert-molding the stamped insert conductor in a base and cutting an unnecessary joint, molding a connector part in the base, connecting a magnetoelectric conversion device to the insert conductor, mounting surface mount electronic components on predetermined positions of the insert conductor by using positioning parts formed on a frame formed in the insert conductor existing between a plurality of the bases, cutting the frame formed in the insert conductor, and inserting the base into a case, heat-caulking a case end, and fixing the base and the case mutually.
According to the tenth aspect of the invention, there is provided a method of manufacturing a rotation sensor comprising the steps of stamping an insert conductor into a predetermined shape, insert-molding the stamped insert conductor in a base and cutting an unnecessary joint, molding a connector part in the base, connecting a magnetoelectric conversion device to the insert conductor, mounting surface mount electronic components on predetermined positions of the insert conductor, making a resin injection port near the magnetoelectric conversion device and molding a case, and inserting the base into the case, heat-caulking a case end, and fixing the base and the case mutually.